Greetings, I have troubles with my car which is Honda Inspire UA1 with G20A engine, but since is a Japanese market car and there is no forum about it I have to ask you, because the model is similar to Acura TL UA2 and G25A engine. A couple of days ago I've found out that I have a strange problem. I was stuck in a traffic jam when suddenly my battery and overheat lights turned on and the idle was poor. I thought it may be overheated so I've stopped at the next gas station but it was all good. There were no signs of overheating and so on. I have an on-board diagnostic called Infoboard which reads all the data from ECU. The temperature shown by ECT sensor was in normal range and my temperature dial was in the middle so there was no overheating. However, I've saw that the alternator is not charging correctly when these lights turn on - only 12.5V. When I accelerate to a higher RPM eg. 2500 the lights turn off and the alternator is charging between 13.8V-13.9V. After a while even pushing on the throttle doesn't solve my problem - lights are on and alternator is not charging. If I let my car to cool down for a couple of hours everything is working perfectly. When cold it charges between 14.00V-14.10V. Again when it reaches normal working temperature the problem occurs.

 

Check to see if your harmonic balancer or crankshaft pulley is on its way out. Usually the inner ring that drives the alternator belt separates and causes not charging symptom at certain engine rpm. Would love to see pics of this Inspire UA1. Post pics if you can!

 

Here are some photos of Inspire UA-1.

Update:

Yesterday I've started the car just to do some charge on the battery until it reaches working temperature when the problem occurs. Strange thing is that there was no such issue when the car is not moving. It reached working temperature and I left it like this for half an hour or even more and everything was okay.

 

That's one clean JDM Inspire! Hopefully the problem went away after the charge. How does the G20A runs, and any pics under hood?